Fix a crash in the Win32 event dispatcher
Fix a crash in the Win32 event dispatcher

Not clearing the timerVec and timerDict containers can cause crashes during
application shutdown when code tries to unregister timers (that were
unregistered in closingDown()).

Reviewed-by: dt

pruiz/wkhtmltopdf-qt,radekp/qt,pruiz/wkhtmltopdf-qt,radekp/qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,radekp/qt,pruiz/wkhtmltopdf-qt,radekp/qt,pruiz/wkhtmltopdf-qt,radekp/qt,radekp/qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,radekp/qt,radekp/qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,radekp/qt,radekp/qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt